Learn what the HAC ratings mean

M-Ratings:

Wireless devices rated M3 or M4 meet FCC requirements and are likely to generate less interference to hearing devices than wireless devices that are not labeled. M4 is the better/higher of the two ratings.

 T-Ratings:

Wireless devices rated T3 or T4 meet FCC requirements and are likely to be more usable with a hearing device's telecoil ("T Switch" or "Telephone Switch") than unrated wireless devices. T4 is the better/higher of the two ratings. (Note that not all hearing devices have telecoils in them).

When wireless devices are used near hearing devices (such as hearing aids and cochlear implants), users may detect a buzzing, humming, or whining noise. Some hearing devices are more immune than others to this interference, and wireless devices also vary in the amount of interference they generate.

Hearing devices may also be measured for immunity to this type of interference. The more immune your hearing aid is, the less likely you are to experience interference noise from wireless devices. Your hearing device manufacturer or hearing health professional may help you find results for your hearing device.

TerraCom offers handsets with different levels of functionality described as follows:

Functionality Level AA includes the functionalities of Level A as well as WiFi.
Functionality Level A indicates a phone that is at least SMS, Camera, Bluetooth, USB, and Data capable.
Functionality Level B indicates a phone that is at least SMS, Camera, and Data capable.
Functionality Level C indicates a phone that is at least SMS and Data capable.
Functionality Level D indicates a phone that is at least SMS capable.
Functionality Level E includes no additional functionalities or functionalities other than SMS.